Originating from many sources, slop oils vary widely in composition and physical properties.
One common factor is that they contain both water and solid impurities, coarse as well as fine. Often the oil and water form a very tight emulsion.
Treatment of slop oils is therefore a tricky task and most of the methods used for their recovery fail in one way or the other. Gravity settling is a slow and often ineffective operation that requires plenty of space and often expensive chemicals. Filter presses can only separate solids from the liquid and have low capacity. Incineration is an expensive process, and the oil is not recovered.
Centrifuging Processing with a three-phase centrifuge has been shown to be extremely economical and efficient. An example of such cost savings and efficiency can be seen throughout the tank cleaning process in an refinery.
Crude oil is stored in tanks ranging in size from 5,000 cubic meters (1.3 mil gallons) to 130,000 cubic meters (34 mil gallons). As time goes by, a wax-like layer consisting of heavy hydrocarbons and inorganic impurities such as sand, rust, and heavy metals builds up on the bottom of the tanks, thereby reducing the utilizable tank volume. Prior to safety inspections, maintenance work, and repair jobs, the tank has to be completely emptied and cleaned. Tanks are cleaned with crude oil, diesel oil, and water. Depending on the size of the tank, up to 1,000 metric tons of residuals remain for disposal or incineration after cleaning. These residuals can be processed using a three-phase centrifuge to recover the major part of the oil, to deliver water stream that can be fed to a sewage treatment plant, and to reduce the volume of the solids phase.
By using a three-phase centrifuge, the transportation, disposal, and incineration of residues, waste etc. are diminished to a minimum as
The recovered oil (up to 90 % or even more) can be recycled in the refinery or processed and utilized for lubrication processes
The volume of residues is reduced to only 10 to 20 % of the original sludge quantity.
Petroleum Solids Control, Inc. is the largest provider of specialized solids, liquids and oil separation rental equipment on the west coast. Since 1956 we have been a family-owned and operated company. Seventy years of experience has enabled us to become experts in providing our customers with tailored solutions for all their separation needs.